JPS6233359B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for continuous twisting of strand-like objects made of wires with a large cross section, such as electric cables.

In the case of conventional twisting techniques for twisting strands of large cross-section - whether this technique is for producing electrical cables or for producing ropes for transmitting mechanical forces. Whatever it is,
A storage drum or a storage bobbin containing individual strands is provided in or on a rotating twisting mechanism, and the individual strands are drawn from this storage drum or storage bobbin and grouped together in the twisting mechanism. guided and twisted into high-quality twisted products in a twisting machine. In this known method, the moment of inertia of the machine is large, which limits the production speed. In addition to this, the installation of this type of device requires a large amount of space, the winding capacity of the winding drum or winding bobbin is limited, and the storage capacity of the storage bobbin or storage drum in which the individual strands are stored. Since there are also restrictions on the length of the product, errors may occur when continuously manufacturing long products.

These difficulties and shortcomings of known production methods can be overcome by reversibly twisting the strands by means of a device in which a forced guide device is provided which rotates for each individual strand in alternating directions of rotation about its axis. Efforts have been made to eliminate (Federal Republic of Germany patent no.
Publication No. 2514033). In this case, the price of the entire manufacturing device is relatively reasonable, the dimensions can be reduced, especially in order to save space, and the large inertial forces caused by rotation do not have to be taken into account as much as before.
With such a device, the preparation time for operating the device can also be considerably reduced.

However, a drawback that arises even with this known device or method is the torsional forces that arise when twisting materials of large cross-section;
In some cases, this can also damage the insulation provided, so that the core of the cable twisted in this way cannot satisfactorily meet the requirements placed on the core.

For this reason, in the present invention, wires made of a single solid wire can be twisted into ropes, cables, etc., and in this case, the insulating layer or corrosion-resistant layer present on the wires can be twisted into ropes, cables, etc. It is an object of the present invention to provide a method and apparatus that do not damage the coating layer.

Such twisting of the wires of ropes, cables, etc. can furthermore be carried out continuously over the entire length with the lowest possible expenditure on mechanical equipment and personnel.

This problem is solved by the present invention as follows. That is, the strands are first guided in one bundle to a first twisting point, and then stretched in the axial direction while passing through a section defined by the first twisting point and the second twisting point. The remainder of the bundle is alternately rotated around the axis and twisted alternately by a conveying device that holds and conveys the bundle and parts of the bundle at intervals in the axial direction.

This twisting method also makes it possible to continuously twist rope-like objects of arbitrary cross-sectional size. In this case, there is no need to rely on the rotating twisting devices conventionally used for this type of purpose. By twisting the strands in an extended state and causing them to leave the twisting device in an extended state, the twisted strands are introduced into the next processing step in a prepared state. In this way the overall manufacturing process is significantly simplified.

Furthermore, this method allows selection of any twisting style. That is, by constantly rotating the twisting device in one direction, the individual twisted strands are entangled and formed into a twisted bundle. In this twisting technique, the essential twisting style may cause difficulties in some cases. In electrical cables, it is often necessary to form branch points or connection points, but there is also a requirement that the strands to be connected do not become untwisted. In this case, the method described above is improved by other features according to the invention as follows. That is, the rotation of the twisting device can be selected in one direction or the other, at least 180°, especially 360°.
Twist the strands in the opposite direction of ゜. The alternatingly twisted strands are not intertwined with each other and therefore do not need to be shaped so that they can be unraveled for connection purposes. Access to the individual strands is possible from any position on the cable or rope after lifting the bundle. This type of strand formation is known per se in high voltage cables for producing concentric shielded or neutral conductors, but alternately stranded materials are formed in concentric layers, i.e. twisted in opposite directions. However, a bundle of core wires made of individual strands is not formed.

According to another configuration of the invention, the angular velocity at which the strands are twisted in one direction and then in the other direction during passage is
It is chosen that the strands are alternately twisted first several times in one direction and then several times in the other direction. A well-known technology for the production of telecommunication cables or power cables where very small cross sections are important is:
The produced twisted bundle has high stability, and has the advantage that individual strands do not come off from the twisted bundle even during winding and unwinding. The number of strands twisted in alternating directions of rotation and at different rotational speeds can be chosen arbitrarily;
The book or books, optionally including the control conductor, are assembled into bundles and then twisted with opposite twists. Other embodiments of the invention are also advantageous, in which the strands twisted along a predetermined length are superimposed with a second twist before this length is achieved. For example, in the production of cables, especially when the material cross-section is large, this significantly increases the production speed.

In other embodiments of the invention, it is also possible to combine the aforementioned twisting patterns depending on the length of the cable or the length of the material, resulting in different twists in sections over the entire length. .

In another embodiment of the invention, the continuous body of twisted strands is held in an extended state over a certain length after the twisting process, providing additional fixation during the production of ropes or cables. There is no need to wrap it. The application of certain layers to the conventional structure likewise takes place in a known manner and requires no additional working steps for fixing the twisted strands.

It is also advantageous to orient the strands individually before introducing them into the twisting point. For example, it is particularly advantageous when the wire is formed into a solid fan shape. This is because this type of wire has particularly high rigidity, and is naturally twisted during manufacturing and, in some cases, during winding and unwinding during insulation treatment.

Another configuration of the invention for producing strands of large cross-section consists of twisting sections of individual strands held in an elongated state, and then twisting the next section in a way that is different from the previous section. Twist in direction and number of twists. This facilitates adaptation to the requirements set by the different intended uses of the twisted strands.

In other embodiments of the method according to the invention, the first
and the second twist point, tightening jaws or tightening tongs are fixed to an endless chain or belt one after the other at intervals along the axial direction,
and this clamping jaw or clamping tong axially grasps a part of the bundle of strands and moves axially with this bundle, and during the axial movement of the bundle, the axis of the bundle is A conveying device that rotates while alternating rotational directions is provided around the device. These axially interlocked clamping jaws or clamping tongs ensure reliable guidance of the strands during the twisting process and, in addition,
It also ensures that the torsional forces necessary for twist formation are transmitted without damage to the objects passing through. The tightening jaws or tightening tongs can be rotated in one direction, but they can also be rotated around the axis in alternating directions of rotation and at different speeds of rotation.

The spacing in the passing direction between the twisting points and the first and last clamping jaws is advantageously selected to be reversible, making it possible to alternately twist strands of any diameter and cross-section and profile. be. Furthermore, the number of twists can be changed arbitrarily, and thus twisted strands can be produced for use in any range of applications.

In special cases, the tightening jaws or tightening tongs may be kept open during operation or released only occasionally.
It is also advantageous to bring it into a displaced position relative to the wire and then close it again. In this case, the tensioning joint transmits torsional forces intermittently for the purpose of twist formation, which results in the twist formation process occurring at unequal speeds.

In a further embodiment of the invention, the tightening jaws or tightening tongs consist of members arranged opposite each other in pairs and protected against torsion. Clamping jaws or clamping tongs, known as so-called clamping conveying devices, frictionally hold wires guided in bundles over any selectable length, so that, for example, insulated wires can be bonded to metal. In comparison, it has little shape stability, which prevents its surface from being damaged by shear forces. The length of the tightening jaw or the tightening tongs can therefore be adapted to the permissible surface pressure of the rod by means of other embodiments of the invention.

The tightening jaws or tightening tongs themselves can be fixed to the rolling chain and form a crawler mechanism with the chain on both sides of the bundle or on both sides of the twisted strands. In this case, the chain is driven at a speed equal to the conveying speed of the bundle of strands, for example an electric motor is used to drive the chain, the transmission of force taking place by means of a gear system. At the same time, the tightening transport device consisting of the tightening jaw, the tightening tongs and the chain rotates in alternating directions around its axis, the drive of which is a direct current motor with a reversible drive. The drive motor for the chain can be provided either within the rotating part of the device or outside the stationary part. If the motor is installed in a stationary part of the twisting device, its rotational speed is superimposed by the reduced angular speed of the rotating conveying device.

In the embodiment according to the invention, a so-called tensioning conveyor is provided, which conveys the strands which are drawn out from a stationary storage drum and which then impart a twist to the aligned strands. The storage capacity is equal to the guide length resulting in an extended storage. However, when trying to increase the storage capacity of the twisting device, the first
It is advantageous to provide a second clamping jaw conveyor behind the clamping jaw conveyor, in which case both conveyors rotate with the same angular velocity and direction of rotation. The distance between the first and second clamping jaw conveying devices is of course limited, but can be freely selected. A second twisting point is provided at the rear of the second conveying device. In this configuration, the storage capacity of the elongated store formed by both tensioning joint conveyors as well as both twisting points is variable, i.e. by moving the mechanical parts forming the twisting section the storage capacity can be increased. It also becomes smaller.

If, in the embodiment of the invention, two clamping jaw transport devices are used one after the other, it is also advantageous to rotate the two transport devices in opposite directions.
Rotating both conveyors with equal frequency gives twice as much twist to the strands.

A further configuration of the twisting method according to the invention provides that the twisting method likewise rotates behind the second rotating conveyor in the passing direction, thus increasing the storage capacity or holding the twisting length in an extended state and adding A third transport device is provided which is fixed to eliminate loose wrapping.

If a fixed stationary conveyor - a rotating rotary conveyor - a fixed stationary conveyor are arranged one after the other in the passing direction, the twisting is The speed at which the bundle passes from one conveyor to another is reduced. but,
Since the individual clamping jaws or clamping tongs are frictionally connected to the bundle, the speed of movement of these elements from one conveying device to another in the direction of passage differs. Therefore, all tightening conveyor devices should be
It is particularly advantageous to drive with the translation speed of the clamping jaw in the last conveying device. The clamping jaws or clamping tongs of the first stationary transport device, which are fixed, and the clamping jaws or clamping tongs of the rotary rotary transport device can be slid in its guide run in the passing direction against the force of a return spring. It is advantageous if the These members move within the guide travel mechanism during the tightening process by the amount of work progress expressed by the formula S=(f-1)L (mm). In this case, f is a factor and L is the distance over which the clamping jaw moves in the conveying device under the clamping action. Since all tensioning conveyors are driven with the same translational speed,
The twisting stroke takes place at the relative speed of the tightening jaw with respect to the guiding travel mechanism. This relative speed is caused by the towing of the respective subsequent clamping jaw conveyor.
Furthermore, only the last clamping conveyor in the production line exerts a pulling force on the twisted strand, while the other conveyors are only dragged. The drive of the front tensioning jaw transport device serves to limit the traction force on the tensioning jaw, ie to make this force very small.

Next, the present invention will be explained in detail with reference to drawings showing embodiments.

Wire 1, for example, fan-shaped wire 1 of an electric cable
is drawn from a stationary storage 2 and fed to a first twisting point, a twist-forming nipple 4, via a so-called roll straightening device 3, which corrects the corrugation or curvature of the wire, making it smooth and straight. In this nipple 4, the individual strands 1 are assembled into bundles and fed to a conveying device 5, which is also a twisting device, and is arranged at the rear in the passing direction. This conveying device 5 consists of a tightening jaw or tightening tongs 7 fixed to a rotating chain 6, which hold a bundle 1a of strands 1 together, as shown in FIG. do. The drive of the chain 6 takes place via a schematically illustrated motor 8, which in this embodiment rotates together with the chain and the tensioning jaw in alternating directions of rotation about an axis, ie in the direction of the arrow. Of course, the rotation is performed continuously in one direction during normal twisting. A machine frame 10 supporting the chain 6, the tightening jaw 7, the motor 8 and the turning roll 9 of the chain is supported by two bearings 11 and 12. The drive takes place, for example, by a belt or chain drive 13 via a gearing 15, for example by a direct current motor 14 with a reversible drive. To ensure synchronization of the chain drives, a chain drive 16 is provided which is a link between the upper and lower chain drives. The rear second twisting point, the twist-forming nipple, is designated by 17. A retaining band 19 is attached by means of a band spinner 18, which is shown schematically.

In the manufacturing process, individual strands 1, for example solid insulated sector-shaped cores of electrical cables, are fed to a straightening device 3 from a stationary storage 2, for example a drum or a bobbin. This straightening device 3 consists of rollers or rolls which are respectively disposed at a displacement, through which the straightening is guided and, in the case of sector-shaped cores, oriented and fed to the twist-forming nipples 4. The strands are gathered into a bundle within the twisting nipple 4 and introduced into the conveying device 5 as the bundled strands 1a. The tightening jaws 7 provided in pairs on both sides of the bundled strands 1a grip the strands integrally after closing, guide the gripped strands through a conveying device, and secure the ends of the device. Open it again. During the passage through the conveying device, the machine frame 10 with the tensioning jaws rotates and - due to the frictional connection between the tensioning jaws and the strands - a twist is imparted to the strands guided by the nipples 4. . Depending on the number of twists carried out for the purpose of giving the strands a twist in one direction and then in the other direction, the strands are given a twist in the known wave pattern or a so-called SZ-twist. The strands are then twisted in one direction in the sections of the two nipples, then the direction of rotation is changed and the wires are twisted in the other direction in the corresponding sections. The clamping jaws 7 hold the strands securely during guidance, so that an additional twist is imparted to the strand when the strands twisted between them are led out. That is, the strands guided in the drawing direction through the twist-forming nipples 17 are finally twisted in the manner of double-twisted strands. Here, the twisting process according to the present invention is performed using a band spinner 18 (schematically shown), as is well known, in order to prevent the finished wires from loosening after being twisted, or to continue another processing step in succession. held in a spiral shape. An extrusion molding machine and a winding device (not shown) can be connected to another continuous work process up to the cable finishing at the front in the guiding direction.

Due to the spaced clamping jaws 7 on the drive chain 6, the effective length of the twist is not constant. That is, the distance between the twist-forming nipple 4 and the first clamping jaw holding the bundled strands 1a is not constant, but varies by the distance between the two clamping jaws. For a given product, it is therefore advantageous to have the conveying device work with a constant effective length.

Such an embodiment is shown in FIG. In this case, unlike the embodiment shown in FIG. 1, the rotating rotational tightening jaw conveying device 20 is moved forward and backward in the passing direction, with the stationary tightening conveying device 21 fixed at the front and the fixed stationary tightening conveying device 21 at the rear. A Joe transport device 22 is provided. The three clamping jaw conveyor devices are constructed in essentially the same way, the conveyor device 20 schematically shown corresponding to that in FIG. 1. However, an important difference from the embodiment having a single tightening and conveying device is that the wire 24 drawn out from the storage section 23 is straightened by a roll straightening device 25;
After being bundled in the nipple 26, the bundles are supplied to the fixed stationary clamping machine transport device 21, where they are held in a bundled state without being rotated around the axis. The point at which the bundle leaves the conveying device 21 becomes a first twisting point and is supplied to the rotary tightening joint conveying device 20 which rotates to perform a twisting action in the bundled state 27. By correspondingly adapting the opening and closing times of the tensioning jaws of the tensioning jaw conveying devices 21, 20, it is ensured that a constant length of twist formation takes place at each time. This point also applies to the second twisting point, at which point the opening and closing times enter the rear conveyor 22, which is synchronized with the rotating rotary conveyor 20. In this way, fluctuations in the effective length of the twist due to the stationary twist-forming nipple in FIG. 1 and the tightening jaws spaced from the nipple and opening and closing at predetermined time intervals are avoided. Fixed stationary clamping conveyor device 2
At the rear of 2 is a band spinner 28 in the usual manner.
This band spinner winds one or multiple bands around a wire in a spiral twist. Fixed stationary clamping conveyor device 2
2 acts as a tension crawler device, while the conveying devices 20, 21 are pulled by strands.

In the arrangement according to FIG. 2, which shows the twisting with one rotating rotary conveyor and two fixed stationary conveyors, the strands are twisted into bundles so that the conveyor can be transferred from one conveyor to the other. The speed of passage of the bundle into the device is reduced. Since the individual clamping jaws or clamping tongs are frictionally engaged, this also changes the speed of passage from one conveying device to the next. Therefore, in the configuration of the present invention,
It is advantageous to drive all clamping jaw conveyors with the translational speed of the clamping jaw in the last conveyor.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a first embodiment of the present invention,
FIG. 2 is a diagram showing a second embodiment. DESCRIPTION OF SYMBOLS 1... Element wire, 2... Storage part, 4... First twisting point, nipple, 5... Conveying device which is also a twisting device, 6... Chain, 7... Tightening jaw or tightening tongs, 17... The second twist point, the nipple.

Claims (1)

[Claims] 1. In a continuous twisting method for a strand-like object made of wires with a large cross section, such as an electric cable, the wires are first guided in one bundle to a first twisting point, and then , the bundle is extended in the axial direction while passing through a section defined by the first twisting point and the second twisting point, and a part of the bundle is held and conveyed at intervals in the axial direction. A method for twisting a strand-like material, characterized in that the remaining bundles are alternately rotated around an axis by a conveying device and twisted alternately. 2. A twisting method for a strand-like article according to claim 1, wherein the strands are twisted reversibly through at least 180°, particularly 360°. 3. A twisting method for a strand-like article according to claim 1, wherein the strands are twisted by SZ-twisting. 4. Claims 1 to 3, characterized in that a second twist is superimposed on the strands twisted along the above-mentioned section by alternating the direction of rotation after the wires have left this section. A twisting method for a strand-like article according to any one of the preceding paragraphs. 5. The method according to any one of claims 1 to 4, wherein the twisted strands are held in a stretched state over a predetermined section after the twisting at the second twisting point is completed. Twisting method for strands. 6. A method for twisting a strand-like article according to any one of claims 1 to 5, wherein the strands are individually aligned before being introduced into the first twisting point. 7. In a continuous twisting device for a strand-like object consisting of wires with a large cross section, such as an electric cable, in the section between the first and second twisting points, there are A clamping jaw or clamping tong is fixed to an endless chain, which clamping jaw or clamping tong axially grasps a part of a bundle of strands, moves along with this bundle in the axial direction, and A twisting device for strand-like objects, characterized in that during the movement, a conveying device is provided which rotates in conjunction therewith with alternating directions of rotation about the axis of the bundle. 8. The twisting device for a strand-like article according to claim 7, wherein the tightening jaw or the tightening tong conveyor rotates at different rotational speeds around an axis. 9. A twisting device for strand-shaped articles according to claim 7, wherein the spacing in the passing direction between the twisting points and the first and last tightening jaws or tightening tongs is variable.